Emergent subtype of hepatitis E virus genotype 3 in wild boar in Spain.

Wild boar (Sus scrofa) is considered as the main wildlife reservoir of zoonotic hepatitis E virus (HEV) genotypes. The aim of this study was to evaluate the circulation of HEV in free-ranging wild boar in the Doñana National Park (DNP), Spain. Blood samples were collected from 99 wild boar in the DNP during 2015. Sera were analysed in parallel using indirect ELISA and real-time RT-PCR. A total of 57 of the 99 tested animals (57.6%; 95%CI: 47.8%-67.3%) had anti-HEV antibodies, indicating that this virus is widespread in wild boar in the DNP. HEV RNA was detected in one animal and phylogenetic analysis showed that the sequence isolated belonged to subtype 3r. The results suggest a potential risk of zoonotic transmission of this novel HEV-3 subtype, which could be of public health concern. Further studies are required to assess the role of wild boar in the epidemiology of HEV-3r and to determine the infectivity of this emergent HEV subtype in other species, including humans.